irqchip/ocelot: Add support for Serval platforms

This patch extends irqchip driver for ocelot to be used with an other
vcoreiii base platform: Serval.

Based on a larger patch from Lars Povlsen <lars.povlsen@microchip.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201125103206.136498-6-gregory.clement@bootlin.com

drivers/irqchip/irq-mscc-ocelot.c

@@ -41,6 +41,17 @@ static struct chip_props ocelot_props = {
 	.n_irq			= 24,
 };
 
+static struct chip_props serval_props = {
+	.flags			= FLAGS_HAS_TRIGGER,
+	.reg_off_sticky		= 0xc,
+	.reg_off_ena		= 0x14,
+	.reg_off_ena_clr	= 0x18,
+	.reg_off_ena_set	= 0x1c,
+	.reg_off_ident		= 0x20,
+	.reg_off_trigger	= 0x4,
+	.n_irq			= 24,
+};
+
 static struct chip_props luton_props = {
 	.flags			= FLAGS_NEED_INIT_ENABLE,
 	.reg_off_sticky		= 0,
@@ -171,6 +182,14 @@ static int __init ocelot_irq_init(struct device_node *node,
 
 IRQCHIP_DECLARE(ocelot_icpu, "mscc,ocelot-icpu-intr", ocelot_irq_init);
 
+static int __init serval_irq_init(struct device_node *node,
+				  struct device_node *parent)
+{
+	return vcoreiii_irq_init(node, parent, &serval_props);
+}
+
+IRQCHIP_DECLARE(serval_icpu, "mscc,serval-icpu-intr", serval_irq_init);
+
 static int __init luton_irq_init(struct device_node *node,
 				 struct device_node *parent)
 {